The doctors and nurses in new york hospitals have been truly heroic and on the day the storm hit, the power went out and then the backup power went out too? What they did to save patients gives us the true measure of who they are and abc's david muir tells us their story. Congratulations. Baby cole was just six hours old but hurricane sandy made her entrance too wind gusts shaking the hospital rattling windows and new mom margaret and dad greg. Mom and dad this their rooms as sandy pounded against the hospital. On the 13th floor you could hear the wins howling and it was really strong. Reporter: It was not before nurses told them they would be evacuating. Everyone had to go. It had be chaotic going down. We were lucky. In the stairwells, patients were women who had just delivered were having issues and stop and regroup and at which point we just went by them. Reporter: The evacuation came after the generators at the new york hospital failed. One in the basement flooding. The fuel pump to the other generator, flooded to. The hospital after having sur rhined irene last year had no idea the east river would do so much damage. Respirators shutting down and elevators frozen shut. Outside the hospital the careful moment, the team surrounding every patient especially the tiniest one, this newborn wrapped in a blanket needed help breathing and with the respirators not working this nurse did the work on her own using tiny bags of air to fill the baby's lungs. When we arrived all you could see were the paramedics racing in with plastic sleds. Inside the stairway nurses and doctors careful at every turn. Worried a wrong move could put the critically ill in greater danger. From above the ambulances, a line of them down the block and around the corner, a stunning sight in a neighborhood that had gone dark. These images take on my iphone, 1 of nearly 300 patients rushed to a nearby hospital. This young doctor was inside when the hospital went dark. There was literally like a bunch of people who would just go with each patient. Carry them down the stairs physically. All nice firemen carrying them gurneyed to the sleds. You saw them dripping with sweat and carrying these women that wouldn't walk down the stairs. Reporter: Their first concern were babies in the intensive care unit brought down nine flights of stairs. Paramedics racing to give them oxygen. The hospital source telling me the first move was to assign a treatment of nurses and doctors to every patient, every newborn until that baby had made it out. Nine flights of stairs. That's an extraordinary trip. It's unbelievable even in an elevator. A lot can go wrong once those elevator doors go closed. You're in terms of a free form environment. When you take them down step, lines can slip, tubes can come out so you need a person monitoring every single thing going on with that patient. Reporter: While this was unfolding salasha was home in new york. Her newborn still back at nyu medical center. She called the hospital to make sure everything was okay. Her baby born a month and a half premature with a heart condition had to stay in the hospital for a few more weeks but then mom turned on the news. I was watching closely looking at all the babies coming out watching nurses, stuff like that. Reporter: It took her hours to get into the city in the middle of the hurricane to find her baby girl and when she got into manhattan she was told to go to mt. Sinai hospital and there she was, another baby saved by one of those teams. You all were the welcoming committee that's right. Reporter: Tonight mom looking over her baby relieved and so are margaret and greg who will soon take their new baby boy home. So a lot to be thankfulor tonight. Very, very much. This will be a very special thanksgiving. Reporting in abc's david muir. And we have had a medical question of a different kind today, people asking a lot. What does the residue of this storm? Is it contaminated? What's in the mud? What's in the water? Dr. Richard besser, by the way, former head of disaster preparedness for the cdc is here because he went out to do some tests that's right. And got some answers. I wanted to show you why you have to be so incredibly careful whether the floodwaters are in your basement or on the street. I went down to manhattan to collect a sample and to protect myself I collected it using gloves and wearing heavy red rubber boots. I took it to the ambient group lab which specialized in water testing and the water looked clear but look at this. This is testing for bacteria. It glows purple if it contains sewage and our sample will know tomorrow whether that had sewage in it. Again, this looked clear. It did. It did. It smelled overwhelmingly like gasoline so you knew something was wrong with that to begin with but the bottom line is any food that has come in contact with floodwater, you have to get rid of it. There's no other way to be safe. You think if it's packaged up or in a can, you can keep it around. There's no way to adequately clean that. If you have to clean something, what's the best way to do it. Well, you want to wear gloves and boots and you can wash it off in a diluted bleach solution. We have that information on abcnews.Com. Another big question coming in, especially some of these communities, as we know, without power, drinking water and you're going to be testing that, as well, tomorrow. I am. All right, dr. Richard besser on the case for us tonight. Thank you, rich.

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